We have continued or initiated several collaborations aimed at exploring and manipulating biological samples with the Nanomanipulator. We continue to work with Eric Henderson, who has brought fruit-fly chromosome samples and examined them. He will send a student here with a sample this spring to attempt to cut the chromosomes at user-specified locations. We have continued our investigations into tobacco-mosaic virus particles. We have experimentally determined parameters for a model that describes the mechanical stiffness and resilience of the particles. We are writing up these results for publication, which will conclude our studies into this particular virus unless another collaborator shows interest in continuing the work. We have begun collaboration with Forrest Ferrari (a student under Jude Samulski at the UNC Center for Gene Therapy). We have imaged and manipulated adeno virus particles; pushing them together and separating them, denting them, and forming clusters. Adeno virus particles are used as vectors in gene therapy: they can be filled with genetic material which they deposit inside cells. We will study the adhesion of the particles to different parts of cells in order to better understand how and where they enter the cells. A new collaboration with Katrina Forest from Scripps Institute is studying pili fibers, which are the fibers used by bacteria to attach themselves to cells. Her group is studying the structure of these fibers, in order to determine the packing order of the components that make up the fibers. Using adhesion mapping with a functionalized tip, we hope to be able to determine the distance between endpoints of these units, thus determining the packing density. We will also study the adhesion of the fibers to each other and to different substrates, using the lateral force measurement capabilities of our new Topometrix AFM. The ability of the atomic force microscope to image in fluid allows us to examine virus particles in vitro; we are pushing forwards to achieve the ability to do non-contact mode imaging in liquid.